Abstract: This article concerns the diptych constituted by the two liminal scenes of Book II, in which Jean-Jacques has just left Geneva : dinner with the abbé Pontverre and his meeting with Madame de Warens. Based on the connection between « conversion » and « conversation », this article studies different forms of conversation : false, between Jean-Jacques and the abbé ; almost mute and autobiographical with Madame de Warens ; and, finally, intertextual for the reader.